SCIENTIA SINICA Informationis, Volume 49, Issue 7: 932-938(2019) https://doi.org/10.1360/N112018-00012

A SAR-ADC switching scheme for bioelectrical signal with high energy efficiency

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  • ReceivedJan 11, 2018
  • AcceptedMar 27, 2018
  • PublishedJan 16, 2019


A flexible electrode is highly suitable for the acquisition of bioelectric signals. After the signal is acquired, an LSB-first SAR-ADC can be used to quantize it to reduce the power consumption. This paper proposes a new LSB-first algorithm. On the basis of previous advantages, the proposed algorithm can avoid the additional power consumption in certain situations. In comparisonwith the traditional algorithm, the proposed algorithm achieves a 98.8% reduction in power consumption when quantifying ECG signal.

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  • Figure 1

    Proposed 10-bit SAR-ADC structure

  • Figure 6

    (Color online) Comparison with other algorithms in power consumption

  • Table 1   An example for the quantitative process
    Bitcycles DIR $D$[10:6~$D$5[4:1] 4:0 $\Delta~D(D_5)$
    1 0 01111[1111]11111
    2 1 [01]1111[0000]11111
    3 1 [01]1111[0001]11111 1
    4 1 [01]1111[0011]11111 3
    5 1 [01]1111[0111]11111 7
    6 1 [01]1111[0101]11111 5
    7 1 [01]1111[0100]11111 4

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